JP3177416B2 - Injection molding equipment for coating resin product recycling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the recycling of resin products, for example, coated resin products such as bumpers, side moldings or CD-ROMs used as functional parts for decoration and cushioning of automobiles and the like. The present invention relates to a method and an injection molding apparatus for recycling coated resin products.

[0002]

2. Description of the Related Art In recent years, the recycling of resin products has been called out due to an increase in environmental issues and interest in resource recycling. For example, even in the automotive industry, there is a problem in the process of producing resin products such as bumpers and side moldings. Attention has been focused on recycling resin products separated and recovered from defective products and end-of-life vehicles.

[0003] Such resin products such as bumpers and side moldings are often coated on the surface of the products in order to improve appearance and quality. For example, on the skin of a bumper, a coating film is formed on a resin material of a thermoplastic resin such as a polypropylene resin via a primer layer made of a thermoplastic resin such as a chlorinated polyolefin resin. This coating film is a thermosetting resin such as an amino polyester type, an amino acrylic type, a polyester urethane type or an acrylic urethane type resin, and these resins are in a liquid state before the curing reaction, but a crosslinked structure is provided by a baking coating process. Is done. This is because of its strong and dense structure, the coated resin bumper has excellent chemical resistance, heat resistance, scratch resistance, weather resistance and surface gloss.

However, if the painted bumper is crushed and reused as it is, a coating film piece is mixed with the polypropylene resin material constituting the material of the resin product, and the polypropylene resin mixed with the coating film piece is mixed. In the molding process using the material, the coating film pieces impede the fluidity of the molten resin and cause molding defects such as "burn", "weld mark", and "bubbles" in the resin product. There are inconveniences such as a coating film piece that has emerged on the surface impairing the appearance of the resin product.

[0005] Further, since the coating film piece is a thermosetting resin and the polypropylene resin serving as a base resin is a thermoplastic resin, there is almost no interaction between the coating film piece and the base resin, and Uncoated film pieces prevent kneading and integration in the recycled resin, significantly reduce the mechanical properties of the recycled resin product, and greatly limit the application range of the recycled resin product.

For this reason, when recycling a coated resin product, it is necessary to remove the coating film. As an apparatus for removing the coating film of the resin product, Japanese Patent Application Laid-Open No. 5-33794 has been proposed.
Japanese Patent Laid-Open Publication No. 1 (1993) -123, and an apparatus for peeling a synthetic resin surface shown in FIG.

The peeling device includes a pair of transport rollers 101
The resin product, for example, the side molding 102 is transferred between the rotating bodies 103 and 104 made of a foaming synthetic resin, and the conveying speed V of the side molding 102 is reduced by the rotating bodies 103 and 10.
By setting the rotation peripheral speed to be lower than the rotational peripheral speed of the side molding 1, cutting and high frictional force are applied to the coating film 102 a and the double-sided tape 102 b of the side molding 102.
02, the coating film 102a and the double-sided tape 102b are cut and peeled, and the side molding 102 is carried out to the outside by a pair of conveying rollers 101.

[0008]

However, in this apparatus, rotating bodies 103 and 104 made of a rotating foaming synthetic resin are used.
The rotating bodies 103 and 104
Is brittle, and generates dust, which is not preferable in terms of working environment and is not suitable for bent or curved resin products.

[0009]

OBJECTS OF THE INVENTION It is an object of present invention is therefore the removal efficiency of the coating film, excellent in processing capability, for injection molding painting resin product recycling that enables to obtain high-quality recycled resin products of It is to provide a device.

[0010]

An injection molding apparatus for recycling a coated resin product according to the present invention, which achieves the above object, comprises:
Crushed pulverized material obtained by grinding resin products
The molding material obtained by heating and melting in the
Injection filling into the injection mold through the spill section
In the injection molding apparatus for injection molding, the heating syringe
Molding material feeding section which communicates with the nozzle and the nozzle section.
Pieces of coating film mixed in molding material interposed in the material feeding section
Mesh to prevent the flow of water into the injection mold
The screen mesh has a screen mesh.
Deviation from this center of rotation with the specified position of the shaft as the center of rotation
Screen mesh interposition part of the molding material feeding part rotated
To replace the filter mesh filter
It is characterized by the following.

[0011]

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a relatively resin bumper paint is applied is large parts Of painting resin product recycling method and a coated resin product automobile parts the injection molding apparatus for recycling recovered, if recycled Will be described as an example.

FIG. 1 is a schematic explanatory view showing each step of a method of recycling a coated resin product. In the process, a defective product generated at the time of forming and assembling a resin bumper, and a resin product to be removed from a scrap car and collected. A collecting step a, a preprocessing step b in which metal parts are removed from the collected resin bumper and cut into several parts to obtain a cut material Wa having a predetermined width, and a coating process is performed on the cut material Wa obtained in the preprocessing step b. A coating film peeling step c for peeling and removing the film Wc to obtain the resin material Wb, a crushing step d for crushing the resin material Wb obtained by peeling the coating film Wc, and a crushed material Wd obtained in the crushing step d And a pellet manufactured from a virgin polypropylene resin or the like is added as necessary, and a molding step e for molding a resin product such as a bumper W is performed.
And

Next, each step will be described sequentially. The symbol W shown in the resin product recovery step a in FIG. 1 is a coated resin bumper which is removed from the defective product in the process and collected from the scrap car, and the metal parts are removed. The bumper W is a thermoplastic resin such as a polypropylene resin. It is a coated resin product in which a coating film made of a thermosetting resin such as an aminopolyester-based, aminoacrylic, polyesterurethane-based, or acrylurethane-based resin is formed on a material made of.

The bumper W recovered in the resin product recovery step a and from which the metal parts have been removed is divided into several parts in the pretreatment step b in order to improve the efficiency of removing the paint film in the subsequent paint film removal step c. It is cut. In this processing, for example, a cut material Wa is obtained by cutting into a relatively flat plate shape, further cutting as necessary, and cutting into a strip-shaped flat plate shape or a plurality of vertically split shapes.

In order to obtain the cutting material Wa from the bumper W, FIG.
As shown in the sectional perspective view of the main part, the bumper W can be easily cut by the cutter 2 in a state where the bumper W is held by the support member 1 which is fitted in the recess of the bumper W and engages and holds the bumper W at a predetermined position. can get.

Further, in order to further improve the removal efficiency of the coating film in the coating film peeling step c described later, protrusions such as ribs projecting from the cutting material Wa are removed, and as shown in FIG.
It is preferable that the shape of a be a trapezoidal cross section with the coating Wc side being the short side. In order to obtain a cut material Wa having a trapezoidal cross section, the bumper W fitted and held on the support member 1 is cut by a cutter 2a having a V-shaped blade shape shown in FIG. It is also possible to obtain a trapezoidal cross section having the film Wc side as a short side.

In order to efficiently cut out and flatten the protruding portions such as ribs protruding from the cut material Wa, the protruding portion shearing device 3 can be used. This projecting portion shearing device 3
As shown in the sectional view of the main part in FIG. 4, the support roll 4 includes a pair of opposing support rolls 4 and a shear roll 5. Support roll 4
The shear roll 5 is rotationally driven by a rotary drive device such as a motor.

The shearing roll 5 is shown in FIG.
As shown in the sectional view taken along the line I--I of FIG. 2B, the development of the roll surface is shown in each case, and a shearing blade 5a composed of an annular convex portion meandering smoothly along the circumferential direction is formed on the cylindrical roll surface. Each of the shearing blades 5a is provided in a plurality of rows in the direction of the roll rotation axis at equal intervals through an annular groove 5b meandering smoothly.

The supporting roll 4 and the shearing roll 5 are mutually rotated in the feeding rotation direction so as to pinch and feed out the cut material Wa to be fed in cooperation with each other, and furthermore, the shearing roll 5 is rotated with respect to the peripheral speed of rotation of the supporting roll 4. Each is rotationally driven by a rotational driving device so that the rotational peripheral speed is increased.

Therefore, as shown in FIG. 4, the shearing material Wa having the protrusion We such as a rib inserted between the supporting roll 4 and the shearing roll 5 having different rotational peripheral speeds is composed of the supporting roll 4 and the shearing roll. 5, the protrusion We is inserted into the groove 5b of the shearing roll 5, and is sheared and removed by the smoothly meandering annular shearing blade 5a formed along the roll surface. It becomes a plate shape.

FIG. 6 is a perspective view of a main part of a flattened cutting material Wa whose projection We is cut and removed by the projection shearing device 3 so as to be shaped into a trapezoidal cross section having the coating Wc side as a short side. This can be achieved efficiently by the edge treatment device 6.

The end processing device 6 has a pair of opposed film-side rolling rolls 7 and a resin material-side rolling roll 8. In order to roll and carry out the cut material Wa supplied between the rolling roll 7 and the resin material side rolling roll 8, the cut materials Wa are rotationally driven in directions opposite to each other by rotary driving devices.

A plurality of helical grooves 7a having different helical directions from the center of the roll surface of the roll 7 toward the end of the roll surface are provided on the roll surface of the roll 7 on the coating film side. The groove 7a has an arc-shaped cross section, and is formed such that the press-contact portion with the cut material Wa is sequentially shifted from the roll surface side end side toward the roll surface center side in accordance with the rotation of the coating film side roll 7.

Therefore, the cutting material W supplied between the coating-side rolling roll 7 and the resin material rolling roll 8 which are driven to rotate is used.
a is rolled by these rolling rolls 7 and 8 and spreads also in the rotation axis direction of the rolls 7 and 8. At the time of this rolling, spiral grooves 7 formed on the roll surface of the coating film side rolling roll 7
The end of a, that is, the spiral ridge 7b bites into the surface of the coating film Wc, and the stretching of the rolls 7 and 8 in the rotation axis direction due to the rolling of the cut material Wa on the coating film Wc side is suppressed, and as a result, The contact portion of the resin material Wb with the resin material-side rolling roll 8 is stretched more, and the cut material Wa has a coating film Wc.
The shape is corrected to a cut material Wa having a substantially trapezoidal cross section with the shorter side being the coating film Wc side in which the resin material Wb side is stretched to be larger than the resin material Wb side.

Next, the coating film peeling step c for peeling the coating film Wc from the cut material Wa obtained in the pretreatment step b will be described.

As shown in FIG. 7, the coating film peeling device 9 used in the coating film peeling step c is made of a metal which is opposed to each other, and whose outer peripheral surface is mirror-finished or chrome-plated. It has a material-side roll 10 and a coating-side roll 11.

The resin material side roll 10 and the coating film side roll 11
For example, the rotational peripheral speed of the coating material side roll 11 pressing against the surface of the coating film Wc is larger than the peripheral speed of the resin material side roll 10 pressing against the surface of the resin material Wb such that the respective rotational peripheral speeds are different from each other. The cutting material 1 supplied between the two rolls 10 and 11 is rotated in opposite directions by a rotation driving device so as to apply a pressing force.

Therefore, the cutting material Wa supplied between the resin material roll 10 and the coating film side roll 11 is
1 and a shear shear stress is applied between the resin material Wb and the coating film Wc based on the relative peripheral speed difference between the rolls 10 and 11, and the coating material Wc is removed from the resin material Wb. Peels off.

If the cut material Wa supplied between the coating film side roll 11 and the resin material side roll 10 has a rectangular cross section, the coating material side roll 11 and the resin material side roll 1
The resin material W to which the coating film side roll 11 is pressed against the coating material roll 11 and the resin material side roll 10 to be pressed against by the pressing force of 0
b is deformed so as to protrude outward, and sufficient pressing force by the coating film-side roll 11 and the resin material-side roll 10 is not obtained at the end, so that the resin material Wb and the coating film Wc Since sufficient shear shear stress is not applied, peeling of the coating film Wc is not complete, and the coating film Wc may remain near the end of the resin material Wb.

However, in the pretreatment step b, the resin material W
a is corrected to a trapezoidal cross section in which the coating film Wc side is a short side as described above,
Although the coating film Wc side and the surface side of the resin material Wb are deformed so as to protrude outward due to the pressing force between the resin material side roll 10 and the resin material side roll 10, even at the end, the coating film side roll 11 and the resin material side roll 10 are used. The pressing force is secured, and the resin material W
a sufficient shear shear stress is applied between b and the coating film Wc,
The peeling of the coating film Wc is sufficiently achieved also near the end of the resin member Wa, and the remaining of the coating film Wc is avoided.

In FIG. 1, reference numeral 12 denotes a coating film side roll 1.
1 is a scraper that scrapes off the coating film attached to the roll surface 11a of the coating film side roll 11 in the vicinity of the first roll surface 11a, and the coating film Wc scraped from the roll surface 11a of the coating film side roll 11 by the scraper 12. Is carried out of the coating film peeling device 9 by a belt conveyor or the like and collected. The resin material Wb from which the coating film Wc has been peeled off in the coating film peeling step Wd,
In the next pulverization processing step d, pulverized by a shredder or the like,
It becomes the crushed material Wd.

The crushed material W obtained in the crushing process step d
As for d, a pellet produced from a resin such as virgin polypropylene is added as necessary in the next molding step e, and is supplied to a processing device, for example, an injection molding device 20.

As shown in FIG. 8, a main part of the injection molding apparatus 20 is a cylindrical heating cylinder 21 having a nozzle portion 21a at the tip, and a pulverizing material which is provided at the other end of the heating cylinder 21. Material Wd is stored in the cylinder 2
1b, a heater 25 provided on the outer periphery of the heating cylinder 21, and a hopper 2 for heating and melting the pulverized material Wd supplied from the hopper 22 to the cylinder 21b.
A screw 26 for pressure-feeding the pulverized material Wd supplied to the inside of the cylinder 21b from the nozzle 2 to the nozzle portion 21a and an intervening portion upstream of the nozzle portion 21a of the heating cylinder 21 are provided to filter foreign substances and remove remaining coating film pieces Wc. Nozzle part 21a
And a screen mesh 27 having a rectifying function to increase the kneading degree by increasing the pressure in the cylinder 21b by restricting the flow into the cylinder mesh 21b.

Then, the crushed material Wd put into the hopper 22 by the rotation of the screw 26 is pressure-fed in the cylinder 21b and advances. The crushed material Wd advancing in the cylinder 21b is heated by the heater 25,
While being softened and mixed and melted. The molding material obtained by heating and melting is injected into the injection mold 2 from the nozzle 21a.
After injection filling into the cavity 23a in 3
A resin product, for example, a bumper W is manufactured. At this time, the pressure is increased by the screen mesh 27 while moving forward in the cylinder 21b, the kneading degree is improved, and the coating film piece Wc
A high quality resin product from which is removed is obtained.

FIG. 9 is a cross-sectional view of a main part of another injection molding apparatus, in which parts corresponding to those in FIG.
A large-diameter portion 24a having a large intermediate cross-sectional area is formed at an intermediate position of the molding material supply portion 24 communicating with 1a, and a large-diameter screen mesh 28 is used instead of the screen mesh 27 interposed in the cylinder 21b. By interposing, it is possible to prolong the usable period until it becomes unusable due to clogging due to foreign matter, coating film pieces Wc, etc., reduce the number of screen mesh replacements, increase processing capacity, and improve productivity. Things. In addition, it is preferable to provide a heater 29 on the outer periphery of the large-diameter portion 24a for preventing the molding material stored in the large-diameter portion 24a from hardening.

FIG. 10 is an explanatory view of still another injection molding apparatus. FIG. 10 (a) is a cross-sectional view of a main part of the injection molding apparatus, in which parts corresponding to those in FIG. The different parts will be described.

A disc-shaped screen mesh 30 is disposed between the heating cylinder 21 and the nozzle 21a, while the screen mesh 30 is relatively moved at the center between the nozzle 21a and the injection mold 23. Interposed as possible,
Both ends are in communication with each other by a molding material supply unit 31 which is coaxially and rotatably connected to the nozzle 21a and the axis a of the heating cylinder 21.

The molding material supply section 31 is formed by bending a screen mesh interposition section 31a for interposing the screen mesh 30 in a crank shape eccentric from the axis a. By rotating the angle, the screen mesh interposition part 31a is changed to a two-dot chain line 31 as shown in a sectional view taken along the line II-II in FIG.
a ′, 31a ″... sequentially, and the filtering section of the screen mesh 30 through which the molding material passes is sequentially replaced with a new filtering section.

On the other hand, the heating cylinder 21
A pressure detection unit 32 for detecting the pressure of the molding material b and a drive device for rotating the molding material supply unit 31 at predetermined angles, for example, a stepping motor 33 are provided.

Then, due to the use of the injection molding apparatus, the filtering action portion of the screen mesh 30 is clogged by foreign matters, coating film pieces Wc, and the like, and the flow resistance increases.
When the pressure of the molding material 1b rises and the pressure detected by the pressure detecting section 32 reaches a predetermined value, the stepping motor 33 is operated by the detection signal to rotate the molding material supply section 31 by a predetermined angle, and automatically. It is replaced by the filtering action part of the next screen mesh 30.

The mesh portion 30a of the screen mesh 30 is provided on the front surface of the locus of the mesh interposition portion 31a.

Therefore, the filtering action portions of the screen mesh 30 are automatically and sequentially replaced, and the screen mesh 30
Of the screen mesh 30 can be greatly reduced, the processing capacity can be improved, and the productivity can be further improved. It is preferable that the screen mesh interposed portion 31a be formed to have a large diameter so as to extend the usable period of the filtering section, and hence the usable period of the screen mesh 30, to improve the processing capacity.

FIG. 11 is a cross-sectional view of a main part of still another injection molding apparatus, in which parts corresponding to those in FIG. 8 are denoted by the same reference numerals, and detailed description thereof will be omitted. Only different parts will be described.

A disk-shaped screen mesh 35 having a center of rotation deviated from the axis of the heating cylinder 21 is provided between the heating cylinder 21 and the nozzle 21a. In the central part, they are communicated with each other by a molding material supply part 36 having a large-diameter screen mesh interposition part 36a which interposes a screen mesh 35 so as to be relatively movable. The center of rotation of the screen mesh 35 is provided outside the molding material supply unit 36.

Further, the heating cylinder 21 has a cylinder 21
A pressure detector 37 for detecting the pressure of the molding material b, and a driving device for rotating the screen mesh 35 at predetermined angles, for example, a stepping motor 38 are provided.

Then, the use of the injection molding device causes the filtration portion of the screen mesh 35 to be clogged by the foreign matter and the coating film piece Wc, thereby increasing the flow resistance and increasing the pressure in the cylinder 21.
Each time the pressure of the sensor rises and the pressure detected by the pressure detector 32 reaches a predetermined value, the stepping motor 3
8, the screen mesh 35 is rotated by a predetermined angle, and is automatically replaced with the filtering action part of the next screen mesh 35, so that the replacement work of the screen mesh 35 can be reduced, and the processing capacity can be reduced. Is improved,
Productivity can be improved.

In the above description, the case where a resin product is injection-molded by an injection molding apparatus in the molding step e has been described as an example. However, a die, for example, a T die is used instead of the injection mold of each injection molding apparatus. It is also possible to configure an extrusion molding apparatus and obtain a sheet-like resin molding material, and it is also possible to mold a bumper or other resin products by hot pressing or the like from the sheet-like resin molding material. .

[0049]

As described above, the coated resin product Lisa of the present invention described above.
According to the injection molding equipment for the vehicle, the coating film was peeled and removed
Heat and melt the crushed material obtained by crushing the resin material and remain
Made of resin after further removing coating film pieces by screen mesh
High quality with extremely high coating removal efficiency
Recycled resin products can be obtained and screen mesh
Screen filter by sequentially replacing the
Screen can be used for a longer period of time
Highly productive and inexpensive because the replacement work of the menu is greatly reduced
Recycled resin products are obtained in a wide range of painted resin products
It is a great contribution to recycling.

[Brief description of the drawings]

[1] is a schematic explanatory view of a method for recycling painting resin product

FIG. 2 is a cross-sectional perspective view of a main part explaining a pretreatment step in FIG.

FIG. 3 is a cross-sectional view illustrating a shape of a cut material obtained in a pretreatment process.

FIG. 4 is a sectional view of a main part of a protrusion shearing device used in the pretreatment step.

FIG. 5 is an explanatory view of a protrusion shearing device.

FIG. 6 is a perspective view of a main part of an edge processing apparatus used in a pre-processing step.

FIG. 7 is a perspective view of a main part of a coating film peeling apparatus used in a coating film peeling step.

FIG. 8 is an explanatory sectional view of a main part of an injection molding apparatus used in a molding step.

FIG. 9 is an explanatory sectional view of a main part of still another injection molding apparatus used in the molding step.

FIGS. 10A and 10B are explanatory views of still another injection molding apparatus used in the molding step, wherein FIG. 10A is a cross-sectional view of a main part and FIG. 10B is a cross-sectional view taken along line II-II of FIG.

FIG. 11 is an explanatory sectional view of a main part of still another injection molding apparatus used in the molding step.

FIG. 12 is a schematic explanatory view of a conventional coating film peeling apparatus.

[Explanation of symbols]

 a ‥‥‥‥‥‥ Resin product recovery process b ‥‥‥‥‥‥ Pretreatment process c ‥‥‥‥‥‥ Coating film removal process d ‥‥‥‥‥‥ Pulverization process e ‥‥‥‥‥‥ Molding process W ‥‥‥‥‥‥ Bumper Wa ‥‥‥‥‥ Cutting material Wb ‥‥‥‥‥ Resin material Wc ‥‥‥‥‥ Coating film We ‥‥‥‥‥ Crushed material 10 ‥‥‥‥‥ Resin material side roll 11 Roll on coating film side 20 Injection molding device 21 Heating cylinder 21a Nozzle part 21c In cylinder 23 Injection molding metal Mold 24 ‥‥‥‥‥ Molding material supply section 24a ‥‥‥‥ Diameter section 27 ‥‥‥‥‥ Screen mesh 30 ‥‥‥‥‥ Screen mesh 30a ‥‥‥‥ Mesh section 31 ‥‥‥‥‥ Molding material Supply unit 31a {screen mesh interposition unit 32} pressure detection unit 33 @ step Ping motor 35 ‥‥‥‥‥ Screen mesh 36 ‥‥‥‥‥ Molding material supply unit 36a ‥‥‥‥ Screen mesh interposition unit 37 ‥‥‥‥‥ Pressure detection unit 38 ‥‥‥‥‥ Stepping motor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29B 17/00-17/02 B29C 45/00-45/24 B29C 47/00-47/96 B29B 13 / 00 B44D 3/16

Claims (1)

(57) [Claims] 1. A pulverization method for pulverizing a coated resin product.
The molding material obtained by heating and melting the material in a heating cylinder is
Injection into injection mold via heating cylinder and nozzle
Injection molding equipment for filling and injection molding resin products
Molding material for communicating the heating cylinder with the nozzle portion
A feeding part and a molding material interposed in the molding material feeding part.
Of coating film pieces mixed in the mixture into the injection mold
A screen mesh,
Is set with the specified position of the screen mesh as the center of rotation.
Screen material of the molding material feeding section deviated from the rotation center of the
The mesh interposer rotates to filter the screen mesh
Recycling of painted resin products characterized in that parts are replaced
Injection molding equipment.